Shinya's kind and loving father, Professor Hiraga, is the professor of the country guards.
He and his wife did not see Shinya for 15 years before Episode 20. They were not in Japan.
At Episode 20, he and his wife were in the office looking at the Robots/Genseishins/Phantom Star Gods. Later after the Justirisers' battle, Shinya's parents saw Shinya again.